Flashcards in Third Week of Development Deck (12):
process of establishing 3 germ layers and begins with the formation of the primitive streak
Cells of the epiblast migrate towards to the primitive streak, detach, and slip underneath the epiblast in a process called what?
Mesenchymal cells migrate cranially from the primitive node and pit forming a median celluar cord called what?
the notochordal process, this process aquires a lumen known as the notochordal canal
The prechordal plate will be important in the develpment of the _____ while the notochord will be the basis for the formation of the parts of the ____________________.
forebrain, axial skeleton and spinal cord
What does the cloacal membrane form?
When are body axes formed?
before and during the time of gastrulation
When does the primitive streak regress?
the end of the fourth week
The beginning of the 3rd week of development (gastrulation) is a highly sensitive period for what?
teratogenesis and malformations
high doses of alcohol at the gastrulation stage kills cells in the anterior midline of the germ disc producing a deficiency of the midline in craniofacial structures, fore brain is small
insufficient mesoderm formed in the caudal most region of the embryo , abnormalities in the lower half of body, absent of fused lower limbs (sometimes associated with maternal diabetes)
left and right organ positions are reversed